Abstract Modular multilevel cascaded converters (MMCC) are seen in medium and high voltage applications and have gained attention from industry. This paper presents new control techniques to improve accuracy and control response speed when applied to a delta-connected MMCC- based Active Power Conditioner used for negative sequence and harmonic current elimination. A novel reference current generation scheme combining a notch filter with Decoupled Double Synchronous Reference Frame (DDSRF) is proposed which can extract the negative sequence and a selection of dominant harmonic currents accurately with the minimum time delay. Fast and accurate tracking the extracted reference current is obtained by using a model-based predictive controller with a derivative reference current term. The control strategy is applied to an experimental delta-connected MMCC-APC and the resultant waveforms are shown and analysed, confirming that the grid current quality after compensation has improved significantly.

中文翻译：

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一种用于不平衡负载补偿和谐波消除的基于三角形连接的 MMCC 有源功率调节器

摘要 模块化多电平级联转换器（MMCC）广泛应用于中高压应用中，并受到业界的关注。本文介绍了新的控制技术，当应用于用于负序和谐波电流消除的基于三角形连接的 MMCC 有源功率调节器时，可提高精度和控制响应速度。提出了一种将陷波滤波器与解耦双同步参考框架（DDSRF）相结合的新型参考电流生成方案，该方案可以以最小的时间延迟准确提取负序和选择主要谐波电流。通过使用具有导数参考电流项的基于模型的预测控制器，可以快速准确地跟踪提取的参考电流。